Devices and methods for sleep apnea treatment

ABSTRACT

Devices and methods for improving the coupling between the soft palate and the genioglossus. This may be accomplished, for example, but shortening or stiffening the palatoglossal arch. Improved coupling between the soft palate and the genioglossus may be beneficial to a patient suffering from obstructive sleep apnea (OSA) as a stand-alone procedure, or in combination procedures and devices that cause anterior displacement of the tongue such as hypoglossal nerve stimulation, genioglossus advancement surgery, mandibular advancement surgery, mandibular advancement (oral) appliances, etc.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 15/701,253, filed Sep. 11, 2017, which is a divisional of U.S. patent application Ser. No. 14/937,482, filed Nov. 10, 2015, now U.S. Pat. No. 9,757,564, issued Sep. 12, 2017, which is a continuation of U.S. patent application Ser. No. 13/633,670, filed Oct. 2, 2012, now U.S. Pat. No. 9,205,262, issued Dec. 8, 2015, which claims the benefits of and priority to U.S. Provisional Patent Application No. 61/542,617, filed Oct. 3, 2011. This application is related to U.S. patent application Ser. No. 13/113,524, filed May 23, 2011, now abandoned, and also to U.S. patent application Ser. No. 13/106,460, filed May 12, 2011, now U.S. Pat. No. 9,913,982, issued Mar. 13, 2018. The entire disclosures of all of the foregoing applications are incorporated herein by reference.

FIELD OF THE INVENTION

The embodiments described herein relate, for example, to devices and methods for modifying tissue of the upper airway for the treat of obstructive sleep apnea and snoring.

BACKGROUND OF THE INVENTION

Hypoglossal nerve stimulation has been proposed for the treatment of obstructive sleep apnea. An example of an implantable hypoglossal nerve stimulation system is described in U.S. Pat. No. 7,809,442 to Bolea et al. Published data suggest that response to hypoglossal nerve stimulation varies across subjects. It would be desirable to consider adjunct therapies to hypoglossal nerve stimulation to improve outcomes thereof.

SUMMARY OF THE INVENTION

To address this and other unmet needs, the present disclosure provides, by way of example, not limitation, embodiments of devices and methods for treating OSA and snoring by modifying pharyngeal tissue of the upper airway such as, e.g., the palatoglossus, palatopharyngeus, pharyngeoepiglottis, and/or lateral walls. The methods described herein may be performed as an adjunct therapy or as a stand-alone procedure. For example, the methods disclosed herein may be combined with interventions targeting the tongue such as, e.g., hypoglossal nerve stimulation, genioglossus-advancement surgery, implantable devices that advance the tongue, mandibular advancement surgery, mandibular advancement oral appliances, etc.

Embodiments of the present disclosure improve the mechanical coupling between the tongue, the soft palate and the lateral walls and/or improve the mechanical properties of the connective structures. This may be accomplished, for example, by shortening or stiffening the palatoglossal arch, palatopharyngeal arch, pharyngoepiglottic fold, and/or lateral walls while retaining the integrity and function of the structures.

BRIEF DESCRIPTION OF THE DRAWINGS

It is to be understood that both the foregoing summary and the following detailed description are given by way of example, not limitation. Together with the following detailed description, the drawings illustrate example embodiments and serve to explain certain principles. In the drawings,

FIG. 1 is a schematic illustration of a hypoglossal nerve stimulation system;

FIG. 2 is a schematic illustration showing the structures of the upper airway in a lateral dissection with the palate and mandible shown in medial sagittal section;

FIG. 3 is a schematic illustration showing the structures of the upper airway from the oral cavity;

FIG. 4 is a schematic illustration showing isolated structures of the upper airway in a transverse section;

FIG. 5 is a schematic illustration showing structures of the upper airway in a posterior dissection of the interior pharynx;

FIG. 6 is a schematic illustration showing structures of the upper airway in a posterior dissection of the exterior pharynx;

FIGS. 7A-7F, 8A-8B, 9, and 10A-10B are schematic illustrations of methods for shortening pharyngeal tissue;

FIGS. 11A-11B are schematic illustrations of a tool for use in the method shown in FIGS. 10A-10B;

FIGS. 12A-12B are schematic illustrations of a method for shortening pharyngeal tissue using an implant device;

FIGS. 13A-13G are schematic illustrations of implant devices for use in the method shown in FIGS. 12A-12B;

FIGS. 14A-14B are schematic illustrations of a tool for use in the method shown in FIGS. 12A-12B;

FIGS. 15A-15B are schematic illustrations of an alternative method for shortening pharyngeal tissue using an implant device;

FIGS. 16A-16D are schematic illustrations of implant devices for use in the method shown in FIGS. 15A-15B;

FIGS. 17A-17D are schematic illustrations of a tool for use in the method shown in FIGS. 15A-15B;

FIGS. 18A-18D are schematic illustrations of an alternative tool for use in the method shown in FIGS. 15A-15B;

FIGS. 19A-19F are schematic illustrations of alternative methods for shortening pharyngeal tissue using implant devices;

FIGS. 20A-20D are schematic illustrations of a palatal device; and

FIG. 21 is a schematic illustration of an oral device.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the present disclosure.

FIG. 1 schematically illustrates an exemplary hypoglossal nerve stimulation (HGNS) system 100 comprising internal components 200 and external components 300. The HGNS system 100 is intended to treat obstructive sleep apnea (OSA) by increasing neuromuscular activity of the genioglossus muscle via stimulation of the hypoglossal nerve (HGN) synchronous with inspiration to mitigate upper airway collapse during sleep. Stimulation is generated by an implantable neurostimulator (INS) 210, synchronized with inspiration as measured by the respiration sensing lead (RSL) 220 using bio-impedance, and delivered to the hypoglossal nerve by a stimulation lead (STL) 230. Alternatively, stimulation may be delivered without respect to respiration, negating the need for respiration sensing capability. A programmer system 310 and a therapy controller 320 are wirelessly linked to the INS 210. The programmer system 310 includes a computer 330, a programmer interface 340, and a programmer head 350. The programmer system 310 is used by the physician to control and program the INS 210 during surgery and therapy titration, and the therapy controller 320 is used by the patient to control limited aspects of therapy delivery (e.g., start, stop, and pause).

The implanted components 200 of the HGNS system 100 include the INS 210, STL 230, and RSL 320. The INS is designed to accommodate one STL 230 and one RSL 220. One STL 230 may be used for unilateral implantation and unilateral hypoglossal nerve stimulation. Similarly, one RSL 220 may be used for respiration detection, and may be bifurcated as shown.

The implanted components 200 may be surgically implanted with the patient under general anesthesia. The INS 210 may be implanted in a subcutaneous pocket inferior to the clavicle over the pectoralis fascia. The distal end of the STL 230 (cuff 235) may be implanted on the hypoglossal nerve or a branch of the hypoglossal nerve in the submandibular region, and the proximal end of the STL 230 may be tunneled under the skin to the INS 210. The RSL 220 may be tunneled under the skin from the INS 210 to the rib cage and placed on both lateral sides of the costal margin. The INS 210 detects respiration via the RSL 220 using bio-impedance and stimulates the hypoglossal nerve via the STL 230 synchronous with inspiration.

Further aspects of the HGNS system 100 may be found in U.S. patent application Ser. No. 13/106,460, filed May 12, 2011, entitled OBSTRUCTIVE SLEEP APNEA TREATMENT DEVICES, SYSTEMS AND METHODS to Bolea et al., the entire disclosure of which is incorporated herein by reference.

Activation of the genioglossus muscle by HGNS causes anterior displacement of the tongue, thus opening the retro-glossal airway. Activation of the genioglossus muscle can also cause anterior displacement of the soft palate, thus opening the retro-palatal airway space. Activation of the genioglossus muscle can further cause lateral displacement of the lateral pharyngeal walls, thus further opening the upper airway. In this manner, activation of the genioglossus muscle by HGNS can mitigate different levels and modes of upper airway collapse in OSA subjects.

Although the effect of genioglossus activation on the tongue to open the retro-glossal airway is predictable given the mechanism of action, the effect of genioglossus activation on the soft palate and lateral walls has been heretofore poorly understood and variable across subjects. Nevertheless, in the majority of OSA patients, the soft palate and the lateral walls can contribute to upper airway collapse, alone or in combination with the tongue. Thus, to the extent that activation of the genioglossus by HGNS does not fully mitigate upper airway collapse in a given subject, adjunct therapies as described herein may be considered to address other levels and modes of upper airway collapse, thus potentially improving the subject's overall response to therapy.

The present disclosure provides a number of different therapies that may be used adjunctively with another OSA therapy such as therapies targeting the tongue (e.g., hypoglossal nerve stimulation, genioglossus-advancement, mandibular advancement surgery, mandibular advancement oral appliances, etc.). Alternatively, the therapies described herein may be used as a stand-alone therapy for OSA and/or snoring. To better understand the function of the therapies described herein, it is helpful to consider the anatomical structures of the upper airway and the interactions of those structures.

With reference to FIGS. 2-6, the anatomical linkages between the tongue, soft palate and lateral walls may be explained in more detail. With specific reference to FIG. 2, the hypoglossal nerve (cranial nerve XII) innervates the genioglossus muscle, which is the largest upper airway dilator muscle. Activation of the genioglossus muscle via stimulation of the hypoglossal nerve causes tongue protrusion and anterior displacement of the soft palate, due to linkage via the palatoglossal arch (muscle). Anterior displacement of the soft palate, in turn, can cause tension to be applied to the lateral pharyngeal walls via the palatopharyngeal arch (muscle). Thus, activation of the genioglossus muscle causes opening of the upper airway at the level of the tongue base (retro-glossal space), at the level of the soft palate (retro-palatal space) via the palatoglossal arch, and along the lateral walls via the palatopharyngeal arch.

The anatomical linkage between the tongue base (genioglossus) and the soft palate via the palatoglossal arch, and the anatomical linkage between the soft palate and the lateral walls via the palatopharyngeal arch may be more clearly seen in FIGS. 3 and 4. The palatoglossus muscle forms the palatoglossal arch and the anterior-inferior aspect of the soft palate on either side of the uvula. The inferior and lateral ends of the palatoglossus muscle insert into the genioglossus muscle. Posterior to the palatoglossal arch are the palatine tonsils, and posterior to the palatine tonsils is the palatopharyngeus muscle forming the palatopharyngeal arch and the posterior-inferior aspect of the soft palate on either side of the uvula. The inferior and lateral ends of the palatopharyngeus muscle insert into the lateral walls of the pharynx.

The inferior anatomical linkage between the soft palate and the lateral walls via the pharyngoepiglottic fold may be more clearly seen in FIG. 5. Activation of the genioglossus serves to pull the soft palate anteriorly via the palatoglossal linkage. Anterior displacement of the soft palate serves to apply anterior and lateral (outward) tension to the lateral pharyngeal walls via the palatopharyngeal linkage as well as the inferior lateral pharyngeal walls via the pharyngoepiglottic linkage.

The anatomical linkage between the tongue base (genioglossus) and the lateral pharyngeal walls may be better appreciated with reference to FIG. 6. The anterior-inferior aspect (not visible) of the styloglossus muscles insert into the genioglossus, and the posterior-superior aspect of the styloglossus muscles attach to the styloid process. Similarly, the anterior-inferior aspect (not visible) of the stylopharyngeus muscles insert into the lateral pharyngeal walls, and the posterior-superior aspect of the stylopharyngeus muscles attach to the styloid process. The glossopharyngeal aspects of the superior pharyngeal constrictor muscle also insert into the genioglossus. Thus, activation of the genioglossus serves to apply tension to the styloglossus and the glossopharyngeal aspects of the superior pharyngeal constrictor muscle, which in turn apply lateral outward tension to the lateral pharyngeal walls by virtue of the lateral outward position of the styloid process and the linkage via the stylopharyngeus muscles.

The integrity and extent of the aforementioned linkages may vary across subjects, and thus their response to HGNS therapy may vary accordingly. These linkages are significant because most people who snore or have OSA will have some retro-palatal collapse with involvement of the palate and/or lateral walls. In these subjects, retro-palatal collapse may be due to poor linkage (i.e., poor coupling) between the genioglossus and soft palate, the soft palate and lateral walls, and/or the tongue and lateral walls, possibly the result of tissue redundancy (i.e., slack) in the palatoglossus, palatopharyngeus, and/or pharyngoepiglottic fold, respectively. Tissue redundancy may also be present in the lateral pharyngeal walls due to adipose tissue (i.e., fat) at discrete locations (e.g., fat pads) or distributed throughout the pharyngeal walls, particularly in patients with high BMI, which is common in OSA sufferers.

By modifying these connective structures using the devices and methods described herein, the tendency of the tongue, soft palate, and/or lateral walls to collapse may be mitigated as an adjunct to HGNS therapy or as a stand-alone therapy to treat OSA and/or snoring. The connective structures may be modified using the devices and methods described herein by changing their configuration and/or dimension (e.g., shortening their length) and/or changing their mechanical properties (e.g., increasing their stiffness), for example. Although some embodiments are described with reference to a specific pharyngeal structure (e.g., palatoglossal tissue), the same embodiment may be applied to other pharyngeal structures (e.g., palatopharyngeal tissue) in the alternative or in combination.

With reference to FIGS. 7A-7B, a method of shortening the palatoglossal arch (PGA) is shown schematically. As seen in FIG. 7A, tissue is removed (cut or ablated) from the PGA to form a void 10 limited to the palatoglossal muscle and surrounding mucosa while leaving the rest of the soft palate unchanged. The amount and shape of the tissue removed may vary, to correspond to the amount of PGA shortening desired. In this example, a triangular notch 10 is formed symmetrically on both sides of the PGA. Subsequently, the notches 10 are surgically closed with sutures 12 or the like to bring the cut edges into approximation and thereby shorten the length of the PGA an amount approximately equal to the sum of the bases of the triangular notches as seen in FIG. 7B. A triangular notch may be beneficial because it removes more tissue from the inferior aspect of the PGA (base of triangle) while minimizing tissue removal from the superior aspect of the PGA (apex of triangle), thus enabling shortening of the PGA while minimizing disruption of the remainder of the soft palate. Thus shortening the length of the PGA applies tension to the soft palate and moves it anteriorly relative to the tongue, thereby mitigating retro-palatal collapse (OSA) and tissue vibration (snoring). Any resultant scarring may serve to stiffen the respective tissue structures thus enhancing the effect.

As an alternative, a plurality of tissue sections may be removed and closed from both sides of the PGA as shown in FIG. 7C. In addition, although described with reference to the PGA, the same technique may be applied to other pharyngeal connective structures either alone or in combination. For example, the same technique may be applied to the palatopharyngeal arch (PPA) as shown in FIG. 7D and/or the pharyngoepiglottic fold (PEF) as shown in FIG. 7E. Also by way of example, this technique may be applied to a combination of pharyngeal structures such as the PGA and PPA as shown in FIG. 7F.

With reference to FIGS. 8A-8B, an alternative method of shortening and/or stiffening the palatoglossal arch (PGA) is shown schematically. As seen in FIG. 8A, sutures 22 are bilaterally placed in the PGA in a crisscross fashion. The sutures 22 may generally follow the arcuate shape of the PGA and its width may be limited to the width of the palatoglossal muscle and surrounding mucosa while leaving the rest of the soft palate unchanged. Once in place, the tags ends 24 of the sutures 22 may be pulled relative to the PGA as shown in FIG. 8B to cinch the adjacent tissue length-wise to thereby shorten the length of the PGA and/or stiffen the PGA. Optionally, tissue may be removed from the PGA prior to placement of the sutures 22 as described with reference to FIG. 7A and elsewhere herein. The method described with reference to FIGS. 8A-8B may be applied to other pharyngeal structures in the alternative or in combination.

In some instances, it may be desirable to temporarily shorten or stiffen pharyngeal connective structures to determine if there is a positive effect (in terms of mitigating OSA and/or snoring) before performing any of the permanent procedures described herein. To this end, and with reference to FIG. 9, placations 30 may be formed bilaterally in the PGA to shorten its length, and temporary holding devices 32 may be placed across the placations 30 to retain the foreshortened length. Optionally, more than one placation 30 and holding device 32 may be placed on each side of the PGA to adjust the foreshortened length thereof. The holding device 32 may comprise, for example, a stud with a removable end, similar to what is used for body piercing, such as an earring. With the PGA temporarily held in a foreshortened length, the effect thereof may be studied while the patient is awake (e.g., by awake nasoendoscopy) and/or while the patient is asleep (e.g., drug induced sleep endoscopy and/or, polysomnography). If a beneficial result (e.g., enlarged airway, improved coupling, reduced snoring, and/or reduction in apneas and hypopneas) is observed in any of such studies, the temporary holding device 32 may be removed and a permanent procedure as described herein may be performed to have the same foreshortening and/or stiffening effect on the PGA. The method described with reference to FIG. 9 may be applied to other pharyngeal structures in the alternative or in combination.

With reference to FIGS. 10A-10B, an alternative method of shortening the palatoglossal arch (PGA) is shown schematically. As seen in FIG. 10A, tissue is removed (cut or ablated) from the PGA to form a circular void 40 between the inferior and superior aspects of the PGA while leaving the rest of the soft palate unchanged. The amount (diameter) removed may vary, to correspond to the amount of PGA shortening desired. In this example, several circular holes are formed symmetrically on both sides of the PGA. Subsequently, the holes 40 are surgically closed with sutures 42 or the like to bring the cut edges into approximation and thereby shorten the length of the PGA an amount approximately equal to the sum of the diameters of the circular holes as seen in FIG. 10B. A circular (or other shape) hole may be beneficial because it is confined to the PGA between the inferior and superior aspects of the PGA. The method described with reference to FIGS. 10A-10B may be applied to other pharyngeal structures in the alternative or in combination.

With reference to FIGS. 11A and 11B, a punch tool 50 is shown which may be used to form the holes 40 shown in FIG. 10A. Punch tool 50 includes a handle 52 with an actuation lever 54 to advance a tubular punch 56 through outer tube 57 to engage die 58. When lever 54 is squeezed relative to handle 52, the punch 56 is advanced in outer tube 57. With die 58 fixed relative to outer tube 57, advancement of the punch 56 as indicated by arrow 51 causes the distal cutting edge of the punch 56 to press against the facing surface of the die 58. The tool 50 may be positioned in the oral cavity with the PGA disposed between the distal cutting edge of the punch 56 and the facing surface of the die 58. When so positioned, the lever 54 may be actuated to advance the die, pinch the PGA tissue between the punch 56 and die 58, and form a hole of any desired shape therein. This step may be repeated for each additional hole to be formed in the PGA or other desired pharyngeal tissue structure.

With reference to FIGS. 12A-12B, an alternative method of shortening and/or stiffening the palatoglossal arch (PGA) is shown schematically. As seen in FIG. 12A, an insertion tool 70 may be used to implant devices 60 bilaterally below the mucosa or in the muscle of the PGA as shown in FIG. 12B. The implant device 60 may comprise an elastic structure having an elongated delivery configuration 60A and a foreshortened deployed configuration 60B as shown in FIGS. 13A and 13B, respectively. The implant device 60 may comprise, for example, braided metal (e.g., stainless steel or super elastic nickel titanium alloy) or braided elastomer (e.g., silicone) formed in a tubular shape, with an elongated state 60A and a relaxed state 60B. Thus, when implant device 60 is implanted submucosally in the PGA, the device 60 expands diametrically to engage the surrounding tissue, and shortens longitudinally to stiffen and/or shorten the length on the PGA. Multiple implant devices 60 may be implanted in the PGA, and this method may be applied to other pharyngeal structures in the alternative or in combination.

An alternative implant device 160 is shown in FIGS. 13C-13G. In this embodiment, implant device 160 includes a shaft portion 162 and two anchors 164. The implant device 160 is placed into pharyngeal tissue in a first elongated state 160A as shown in FIG. 13C, and subsequently assumes a second foreshortened state 160B as shown in FIG. 13D. To change from the elongated state to the foreshortened state, a length changing core 166 may be disposed in the shaft portion 162, with access thereto provided by a plurality of slots 163 in the shaft portion 162 as shown in FIG. 13E. The length changing member 166 may comprise a bio-resorbable material, a heat-shrink polymer that shortens upon application of heat, or a dissolvable material that dissolves upon exposure to a solvent (e.g., saline). The shaft portion 162 and anchors 164 may comprise an elastic polymer material such as silicone. Initially, the shaft portion 162 is stretched lengthwise and the core 166 is disposed therein to hold the shaft portion 162 in a stretched or elongated state. Post implantation, the core 166 shortens (by resorbing, dissolving, or exposure to heat) causing the shaft portion 162 to shorten as it returns to its relaxed state. As the shaft 162 shortens, the anchors 164 engage the surrounding tissue causing the tissue to foreshorten and stiffen. The anchors may comprise tines 164 as shown in FIG. 13E, a mesh 164′ as shown in FIG. 13F, or a porous material 164″ as shown in FIG. 13G, wherein the mesh 164′ and the porous material 164″ promote tissue ingrowth for anchoring purposes.

To facilitate insertion of the implant device 60 or 160 under the mucosa or in the muscle of the PGA, an insertion tool 70 may be used as shown in FIGS. 14A and 14B. Insertion tool 70 includes a handle 72 having a lever 74 that may be squeezed as indicated by arrow 73. The lever 74 is mechanically coupled to a flexible outer tube 78, which is retractable relative to an inner member 76 that is fixed relative to handle 72. The outer tube 78 includes a sharpened tip 79 for penetrating into the mucosa and a distal opening for release of the device 60. The distal end of the inner member 76 abuts the proximal end of implant device 60. The outer tube 78 retains the implant device 60 in an elongated, reduced diameter, delivery configuration 60A. When the distal sharpened end of the outer tube 78 is placed under the mucosa or in the muscle of the PGA, the outer tube 78 may be retracted as indicated by arrow 77 by actuation of lever 74 as indicated by arrow 73, thereby releasing the implant device 60 in a shortened, increased diameter, deployed configuration 60B. Thus, the device 60 expands from an elongated delivery configuration 60A to a shortened deployed configuration 60B, thereby stiffening and/or shortening the length of the PGA. The insertion tool 70 may be used to delivery implant device 60 or 160 to other pharyngeal structures in the alternative or in combination.

With reference to FIGS. 15A-15B, an alternative method of shortening and/or stiffening the palatoglossal arch (PGA) is shown schematically. As seen in FIG. 15A, an insertion tool 90 may be used to implant devices 80 bilaterally below the mucosa or in the muscle of the PGA as shown in FIG. 15B. Prior to full insertion of the implant devices 80 in the PGA, the PGA tissues are foreshortened using the insertion device 90, for example, such that the implant devices 80 hold the PGA in a foreshortened state. The implant device 80 may comprise a semi-flexible structure that can flex laterally but resists elongation axially. As shown in FIGS. 16A and 16B, the implant device 80 may include a shaft portion 82 with double-barbed anchors 84 at opposite ends of the shaft portion 82. Alternatively, as shown in FIGS. 16C and 16D, the implant device 80 may include a shaft portion 82 with single-barbed anchors 86 at opposite ends of the shaft portion 82. Anchors 84 and 86 may have a low profile delivery configuration 84A and 86A, and an expanded deployed configuration 84B and 86B, as shown. The anchors 84 and 86 are unidirectional such that they can be easily inserted into tissue in one direction but resist withdraw in the other (opposite) direction. For each implant device 80, the unidirectional characteristic of each anchor is opposite, such that the anchor 84/86 on a first end of the shaft 82 is unidirectional in a first direction, and the anchor 84/86 on the second end of the shaft 82 is unidirectional in a second direction opposite from the first direction. This arrangement of the anchors 84/86 allows tissues surrounding the implant device 80 to foreshorten along the shaft portion 82 while holding the tissues in a foreshortened state to shorten the length of the PGA. The implant device 80 may comprise, for example, an implantable grade permanent polymer, a bio-resorbable polymer (e.g., PLLA, PGA), etc. Multiple implant devices 80 may be implanted in the PGA, and this method may be applied to other pharyngeal structures in the alternative or in combination.

To facilitate insertion of the implant device 80 under the mucosa or in the muscle of the PGA, an insertion tool 90 may be used as shown in FIGS. 17A-17D. Insertion tool 90 includes an inner push member 92, an outer push tube 96, and an intermediate tube 94 with a sharpened distal end. Initially, the intermediate tube 94 extends distally beyond the inner push member 92 and the outer push tube 96, with the implant device 80 contained in tube 94 in a delivery configuration with the anchors 84 folded in. In this configuration, all components 92, 94, 96 of the insertion tool 90 are advanced distally in unison as indicated by arrows A, B, C, and the intermediate tube 94 is inserted into the tissue as shown in FIG. 17A. Once the intermediate tube 94 containing the implant device 80 is advanced sufficiently into the target tissue, the inner push member 92 is advanced distally as shown by arrow A, while the intermediate tube 94 and outer tube 96 remain stationary, thus pushing the implant device 80 out of the distal end of the intermediate tube 94 to deploy distal anchor 84 as shown in FIG. 17B. The outer push tube 96 is advanced distally as shown by arrow C, while the inner push member 92 and the intermediate tube 94 remain stationary, thus engaging the distal flared end of the outer tube 96 against the target tissue causing it to foreshorten as shown in FIG. 17C. The intermediate tube 94 is then withdrawn proximally as shown by arrow B, while the inner push member 92 and outer push tube 96 remain stationary, thus deploying the proximal anchor 84 of the implant device 80 to hold the tissue in a foreshortened state as shown in FIG. 17D. The insertion tool 90 may be used to delivery device 80 to other pharyngeal structures in the alternative or in combination.

An alternative insertion tool 190 may be used to facilitate insertion of the implant device 80 under the mucosa or in the muscle of the PGA as shown in FIGS. 18A-18D. Insertion tool 190 includes an inner push member 192, an outer push tube 196, and an intermediate tube 194. The intermediate tube 194 includes a sharpened tip 195 and a bulb portion 193 having an enlarged diameter. The outer tube 196 includes a slotted distal end defining a plurality of finger-like projections 197 that extend outward when advanced over the bulb portion 193 of the intermediate tube 194. Initially, the intermediate tube 194 extends distally beyond the inner push member 192 and the outer push tube 196, with the implant device 80 contained in the intermediate tube 194 in a delivery configuration with the anchors folded in. In this configuration, all components 192, 194, 196 of the insertion tool 190 are advanced distally in unison, and the intermediate tube 194 is inserted into the tissue. Once the intermediate tube 194 containing the implant device 80 is advanced sufficiently into the target tissue, the inner push member 192 is advanced distally as shown by arrow A, while the intermediate tube 194 and outer tube 196 remain stationary, thus pushing the implant device 80 out of the distal end of the intermediate tube 194 to deploy the distal anchor of the implant device 80 as shown in FIG. 18A. The outer push tube 196 is advanced distally as shown by arrow B, while the inner push member 192 and the intermediate tube 194 remain stationary, thus engaging the finger-like projections 197 of the outer tube 196 against the bulb portion 193 of the intermediate tube 194 and causing the fingers to flare outward. The flared projections 197 then push against the target tissue causing it to foreshorten as shown in FIG. 18B. The intermediate tube 194 is then withdrawn proximally as shown by arrow C, while the inner push member 192 and outer push tube 196 remain stationary, thus deploying the proximal anchor of the implant device 80 to hold the tissue in a foreshortened state as shown in FIG. 18C. The insertion tool 190 may then be removed from the target tissue leaving the implant device in place as shown in FIG. 18D. The insertion tool 190 may be used to delivery device 80 to other pharyngeal structures in the alternative or in combination.

With reference to FIGS. 19A-19F, various implant devices are shown schematically which, in general, improve coupling between the tongue and the soft palate via the palatoglossal arch. In FIGS. 19A and 19B, two implant devices 410 extend from the soft palate, through the palatoglossal arch and into the genioglossus. Each implant device 410 includes a tether member 412 (e.g., multi-filament polymer), and two tissue anchors (e.g., polymer barb) 414 and 416 residing in the genioglossus and soft palate, respectively. The implant devices 410 may be implanted using insertion tool 90 for example, such that it applies tension between the soft palate and tongue via the palatoglossal arch, thereby improving coupling therebetween. In FIG. 19C, a variation of implant device 410 is shown as implant device 420, which functions in a similar manner but eliminates tissue anchors in the tongue in favor a loop of the tether 412.

In FIGS. 19D-19E, two implant devices 430 extend from the soft palate, through the palatoglossal arch and genioglossus, to the mandible. In this embodiment, device 430 includes a tether member 412, a tissue anchor 416 residing in the soft palate, and a bone anchor 418 residing in the mandible. The implant devices 430 may be implanted using insertion tool 90 for example, such that it applies tension between the soft palate and tongue via the palatoglossal arch, thereby improving coupling therebetween. In FIG. 19F, a variation of implant device 430 is shown as implant device 440, which functions in a similar manner but eliminates tissue anchors in the palate in favor a loop of the tether 412.

With reference to FIGS. 20A-20D, a palatal appliance 510 is shown schematically. As seen in the side view shown in FIG. 20A and the front view shown in FIG. 20B, the palatal appliance 510 includes a dentition portion 512, a palatal portion 514, and a connecting arch member 516. As shown in FIGS. 20C and 20D, the dentition portion 512 engages the front teeth, the palatal portion 514 includes two tabs that engage the posterior aspect of the soft palate on either side of the uvula, and the arch member 516 extends along the roof of the mouth to connect the dentition portion 512 to the palatal portion 514. The palatal appliance 510 may be formed of conventional materials used for dental appliances, and may be customized for an individual patient using a boil-and-bite technique or a mold-and-thermoform technique. In use, the palatal appliance 510 keeps the soft palate from falling posteriorly, and may be under-sized to displace the soft palate anteriorly from its normal position. Palatal appliance 510 may be used as a stand-alone therapy in the case of isolated retro-palatal collapse, or used as an adjunct to HGNS therapy in the case of poor palatal coupling.

With reference to FIG. 21, an oral appliance 520 is shown schematically. The oral appliance 520 includes upper and lower dentition portions 522A and 522B, and a spacer portion 524. The dentition portions 522A and 522B engage the teeth, and the spacer 524 resides between the upper and lower teeth as well as the upper and lower lips. An arch member (not shown) may be provided to extend from the spacer along the roof of the mouth. The spacer portion 524 includes a middle portion 526 and two lateral portions 528. The middle portion 526 defines a lumen 527 through which air may flow freely, or into which the tongue may extend (if used in conjunction with HGNS therapy). Similarly, the lateral portions 528 define lumens 529 through which air may flow freely. The lateral portions 528 may include baffles 530 in a serpentine shape, for example, to provide structural support while permitting airflow therethrough. The arch portion (not shown) may also include a flow path in communication with lumens 527 and 529 through which air may flow freely. The dentition portions 522A and 522B secure the appliance 520 in the mouth during sleep, but permits easy insertion and removal of the appliance 520 to/from the oral cavity at the beginning and ending of the sleep period, respectively. Optionally, one dentition portion 522A or 522B may be used. The spacer 524 keeps the mouth open (teeth and lips) to permit mouth breathing, despite the tendency of the mouth to close during sleep. Similarly, the arch portion maintains a flow path for mouth breathing, despite the tendency of the tongue to fall against the roof of the mouth during sleep. The spacer 524 may have a rectangular housing with a serpentine support baffle 530 as shown, or the serpentine support structure 530 without a housing. The oral appliance 520 may be formed of conventional materials used for dental appliances, and may be customized for an individual patient using a boil-and-bite technique or a mold-and-thermoform technique. In use, the oral appliance 520 maintains an open flow path for mouth breathing, despite the tendency of the mouth to close and the tongue to rest against the roof of the mouth during sleep. Oral appliance 520 may be used as a stand-alone therapy in the case of isolated retro-palatal collapse, or used as an adjunct to HGNS therapy in the case of poor palatal coupling.

The adjunct devices and therapies described herein may be used in combination with HGNS therapy, or other therapeutic interventions that directly address retro-glossal collapse. For example, the adjunct therapies described herein may be used in combination with genioglossus advancement surgery, mandibular advancement surgery, mandibular advancement (oral) appliances, etc. Alternatively, the therapies described herein may be used as stand-alone procedures to treat OSA and/or snoring.

Examples of conventional OSA therapies that may be used as an adjunct to HGNS include palate surgeries such as uvulopalatopharyngoplasty (UPPP), palatopharyngoplasty, uvulopalatal flap, and palatal implants (e.g., Pillar® implants sold by Medtronic). Palate surgeries primarily affect upper airway collapse at the level of the palate. As such, these therapies may be considered as adjunct to HGNS in subjects that have residual retro-palatal collapse with HGNS therapy, possibly due to poor anatomical coupling between the tongue and the palate.

From the foregoing, it will be apparent to those skilled in the art that the present disclosure provides, in non-limiting embodiments, devices and methods for treating OSA and snoring by modifying pharyngeal tissue of the upper airway such as, e.g., the palatoglossus, palatopharyngeus, pharyngeoepiglottis, and/or lateral walls. Further, those skilled in the art will recognize that the present disclosure may be manifested in a variety of forms other than the specific embodiments described and contemplated herein. Accordingly, departures in form and detail may be made without departing from the scope and spirit of the present disclosure as described in the appended claims. 

What is claimed is:
 1. A method of treating an upper airway tissue collapse condition of a patient, comprising: implanting at least one tissue engagement member in the patient's upper airway to tighten the patient's upper airway tissue from a first condition of the patient's upper airway tissue to a second condition of the patient's upper airway tissue that has a greater stiffness than the first condition, the patient's upper airway tissue in the second condition conveying anterior movement of the patient's tongue to maintain a patency of the patient's upper airway; and disposing a stimulation device configured for delivering an electrical stimulation to a nerve innervating a tongue protrude muscle of the patient to cause anterior movement of the patient's tongue, wherein the electrical stimulation improves an efficacy of the at least one tissue engagement member.
 2. The method of claim 1, wherein tightening the patient's upper airway tissue includes tightening the patient's pharyngeal tissue.
 3. The method of claim 2, wherein tightening the patient's pharyngeal tissue includes shortening the patient's palatoglossus.
 4. The method of claim 2, wherein tightening the patient's pharyngeal tissue includes shortening the patient's palatopharyngeus.
 5. The method of claim 2, wherein tightening the patient's pharyngeal tissue includes shortening the patient's pharyngoepiglottic fold.
 6. The method of claim 1, wherein the upper airway tissue collapse condition is an obstructive sleep apnea condition of the patient, and wherein the delivering of the electrical stimulation mitigates the obstructive sleep apnea condition.
 7. The method of claim 1, wherein the upper airway tissue collapse condition includes a first tissue collapse at a first location within the patient's upper airway and a second tissue collapse at a second location within the patient's upper airway; and wherein the delivering of the electrical stimulation corresponds to a mitigation of the first tissue collapse at the first location, and wherein the tightening of the patient's upper airway tissue corresponds to a mitigation of the second tissue collapse at the second location.
 8. The method of claim 1, wherein the upper airway tissue collapse condition includes a first tissue collapse at a first location within the patient's upper airway and a second tissue collapse at a second location within the patient's upper airway; and wherein the delivering of the electrical stimulation corresponds to a mitigation of the first tissue collapse at the first location, and wherein an upper airway movement due to the electrical stimulation and the tightening of the patient's upper airway tissue corresponds to a mitigation of both the first tissue collapse and the second tissue collapse.
 9. The method of claim 1, wherein the stimulation device is further configured to modify the electrical stimulation signal in response to receiving a signal from an external therapy controller.
 10. The method of claim 1, further comprising implanting a sensing lead in the patient, wherein the stimulation device is further configured to sense inspirations of the patient via the sensing lead and deliver the electrical stimulation synchronized with the sensed inspirations of the patient.
 11. A system for treating an upper airway condition of a patient, the system comprising: at least one tissue engagement member configured for implantation in the patient's upper airway to tighten the patient's upper airway tissue from a first condition of the patient's upper airway tissue to a second condition of the patient's upper airway tissue that has a greater stiffness than the first condition, the patient's upper airway tissue in the second condition conveying anterior movement of the patient's tongue to maintain a patency of the patient's upper airway; and a stimulation device configured for delivering an electrical stimulation to a nerve innervating a tongue protrude muscle of the patient to cause anterior movement of the patient's tongue; wherein the electrical stimulation is configured to improve an efficacy of the at least one tissue engagement member.
 12. The system of claim 11, wherein tightening the patient's upper airway tissue includes tightening the patient's pharyngeal tissue.
 13. The system of claim 12, wherein tightening the patient's pharyngeal tissue includes shortening the patient's palatoglossus.
 14. The system of claim 12, wherein tightening the patient's pharyngeal tissue includes shortening the patient's palatopharyngeus.
 15. The system of claim 12, wherein tightening the patient's pharyngeal tissue includes shortening the patient's pharyngoepiglottic fold.
 16. The system of claim 11, wherein the upper airway tissue collapse condition is an obstructive sleep apnea condition of the patient, and wherein the electrical stimulation is configured to mitigate the obstructive sleep apnea condition.
 17. The system of claim 11, wherein the upper airway tissue collapse condition includes a first tissue collapse at a first location within the patient's upper airway and a second tissue collapse at a second location within the patient's upper airway; and wherein the electrical stimulation is configured to mitigate the first tissue collapse at the first location and the tightening of the patient's upper airway tissue corresponds to a mitigation of the second tissue collapse at the second location.
 18. The system of claim 11, wherein the upper airway tissue collapse condition includes a first tissue collapse at a first location within the patient's upper airway and a second tissue collapse at a second location within the patient's upper airway; and wherein the electrical stimulation is configured to mitigate the first tissue collapse at the first location, and wherein an upper airway movement due to the electrical stimulation and the tightening of the patient's upper airway tissue corresponds to a mitigation of both the first tissue collapse and the second tissue collapse.
 19. The system of claim 11, further comprising an external therapy controller, wherein the stimulation device is further configured to modify the electrical stimulation signal in response to receiving a signal from the external therapy controller.
 20. The system of claim 11, further comprising a sensing lead configured for implantation in the patient, wherein the stimulation device is further configured to sense inspirations of the patient via the sensing lead and deliver the electrical stimulation synchronized with the sensed inspirations of the patient. 